see also

For one thing, the extra flats are part of 300,000 affordable-housing units Hizzoner says he’ll “create or preserve” — though not until 2026. That is, long after he’s gone.

His original goal was to “secure” 200,000 units by 2024. But this week he bragged that he’ll hit that milestone by 2022, two years ahead of schedule. By shooting for 25,000 a year, instead of 20,000, and stretching the program to 2026, he wants credit for an extra 100,000 low-priced units that — but for him — wouldn’t exist.

Reality check: De Blasio says he’s ahead of schedule because, as of July, his program has preserved 52,309 units and financed the construction of over 25,000 new units.

Yet “preserved” is an inherently soft category that can cover full rehab or modest repairs. Care to bet on whether the city first targeted the easiest units to “save,” leaving tougher ones for later?

Meanwhile, the new construction is the fruit of the 421(a) tax subsidy and similar programs — which long predate this mayor.

And the mayor is ignoring a huge number of “if”s here. For progress to continue at the same pace, the City Council will have to start approving his various rezonings — which it has so far resisted. Many communities are adamantly opposed.

Nor is it clear that the 421(a) program will yield as many new units, now that Gov. Cuomo has forced a rewrite of the rules.

Oh, and the next mayor will have to keep up the work, even as it gets tougher and tougher.

What de Blasio’s reset really means is taxpayer costs of an extra $600 million over the next four years alone, bringing his housing outlays to $1.3 billion per year through 2026.

Yet Gotham’s “housing crisis” won’t vanish, even if the city does hit de Blasio’s magic number by 2026. For decades, after all, mayors have “created or preserved” tons of affordable housing — with no noticeable dent in the “shortage.”

Let’s face it: Cheap apartments simply attract more apartment-hunters, and their supply never catches up. As Mayor Ed Koch said, “If you build it, they will come.” And for de Blasio, that’s a big “if.”